Warming and salinization effects on the deep-water rose shrimp, Parapenaeus longirostris, distribution along the NW Mediterranean Sea: Implications for bottom trawl fisheries

Abstract

The deep-water rose shrimp is a main resource for the GSA 6 bottom trawling fleet. In the last decade, landings have increased without a clear understanding of the causes. This study aims to analyze this trend, potentially related to changes in environmental conditions. Results showed an increase in the species' landings, which spread northwards along the GSA 6. GAM models detected a significant effect of location, time, and depth on the distribution of the deep-water rose shrimp, as did for temperature and salinity. Similar values between landings and LPUE were found throughout, suggesting no effects of fishing effort in time. ANOVA tests showed a significant increase of sea bottom temperature and salinity in time, which were correlated with increasing LPUE values. Then, the trend seems to be related to environmental changes rather than changes in fishing effort. Further research is needed to implement management plans that ensure the resource sustainability.

Keywords: GSA 6; Landings Per Unit of Effort (LPUE); Modeling; Parapenaeus longirostris; Salinity changes; Sea warming.